Some sellers choose to get ID Verified through eBay as an extra sign of security for buyers. When a member gets ID Verified, a third-party company working with eBay confirms the member's identity by cross checking their contact information across consumer and business databases.
You'll see (the ID Verify icon) in verified members' feedback profiles.
Once you have successfully passed the ID Verify process, a $5 fee will be charged to your eBay account.
Whether or not you actually "need" it is up to you. From a buyer's perspective, this may be something I'd look at, but (positive) feedback would seem more important. I've been on ebay for many years, and I have had much success selling, (I have 100% pos feedback), yet I'm not ID verified.